English Reference
adjective · noun

flexible

adj. · n.
US /ˈfɫɛksəbəɫ/ UK /flˈɛksɪbəl/ flex·i·ble

  1. 01 B1 Intermediate

    adj.able to bend easily without breaking.

    adj.capable of being flexed, turned, or twisted without structural failure.

    Simple

    The gymnast used a flexible mat to protect her joints during the routine.

    In context

    Modern aerospace engineering relies on flexible composite materials that can withstand significant aerodynamic pressure without fracturing.

    pliablebendysupple
  2. 02 B2 Upper Intermediate Academic

    adj.able to change or be changed easily to suit new situations.

    adj.capable of being adapted or modified to meet varying conditions or requirements.

    Simple

    My boss is very flexible about which hours I work as long as the job gets done.

    In context

    The software architecture was designed to be flexible, allowing developers to integrate third-party modules without rewriting the core codebase.

    Teacher's tip

    This is the most common sense in professional and academic contexts, often describing schedules, plans, or mindsets.

  3. 03 C1 Advanced Formal

    adj.willing to change your mind or do what others want.

    adj.prone to yielding to the influence or will of others; not obstinate.

    Simple

    He has a flexible personality and usually agrees with whatever the group decides.

    In context

    The negotiator was criticized for being too flexible on key policy points, leading to a compromise that satisfied neither party.

    Teacher's tip

    In this sense, the word can sometimes have a slightly negative connotation, suggesting a lack of firm principles.

  4. 04 C2 Proficiency Technical Technical

    n.an object or material that is able to bend.

    n.a substance or structural element characterized by its ability to flex.

    Simple

    The plumber replaced the rigid pipe with a plastic flexible to allow for movement.

    In context

    The specifications required the installation of high-grade flexibles to accommodate the thermal expansion of the industrial heating system.

    Usage

    Used primarily in engineering or manufacturing contexts.

Usage appreciation flexible

It forces your ankle, knee and hip joints to quickly adjust their movements, keeping them engaged and flexible.

ScienceDaily· 16 Aug 2026

Samsung has largely defined the foldable phone category, but it’s no longer alone in releasing flexible devices.

Ars Technica· 14 Aug 2026

From Middle French flexible, from Latin flexibilis, from flectō (“to bend, curve”). Morphologically flex + -ible.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin Latin flexibilis
Level B2 · Upper Intermediate
Frequency Common
Updated